The aim of this project is to further the rather limited understanding of the biochemistry of the larger and very heterogeneous group of vertebrate lens proteins called beta-crystallins. We believe that elucidation of the structure and function of this family of proteins may be an important step toward understanding the basic biochemistry of the lens and thus the mechanisms involved in human cataract development. Since the beta-crystallins have no known specific biological activity which can be readily used in studying structure-function relationships, we have employed a comparative approach and have isolated and partially chracterized the major beta-crystallin fractions from a wide variety of vertebrates. These studies have given considerable insight into the structure of the beta-crystallin and have demonstrated that at least some components are quite conservative evolutionarily. Our specific objectives involve elucidation of the effects of development, aging and cataractogenesis on the beta-crystallins and of the nature of interactions among the various lens proteins. BIBLIOGRAPHIC REFERENCE: Zigler, J. Samuel Jr. and Sidbury, J. B. Jr.: A Comparative Study of the Beta-crystallins from Six Mammals. Comp. Biochem. Physiol. 53B :349-355, 1976.